package day02;

import java.util.HashMap;

public class MapDemo {
    public static void main(String[] args) {
        // map集合  k-v 键值对
        HashMap<String, Integer> subject = new HashMap<>();
        subject.put("java",100);
        subject.put("C++",90); // 添加元素
        System.out.println(subject);
        subject.remove("java");
        System.out.println(subject);


    }
}
